Article

Magneto-elastic waves in crystals of magnetic molecules

Physical review. B, Condensed matter (Impact Factor: 3.77). 05/2007; DOI: 10.1103/PhysRevB.76.094419
Source: arXiv

ABSTRACT We study magneto-elastic effects in crystals of magnetic molecules. Coupled equations of motion for spins and sound are derived and the possibility of strong resonant magneto-acoustic coupling is demonstrated. Dispersion laws for interacting linear sound and spin excitations are obtained for bulk and surface acoustic waves. We show that ultrasound can generate inverse population of spin levels. Alternatively, the decay of the inverse population of spin levels can generate ultrasound. Possibility of solitary waves of the magnetization accompanied by the elastic twists is demonstrated. Comment: 8 PR pages, 3 figures

0 Bookmarks
 · 
54 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We study the magnetic relaxation rate Γ of the single-molecule magnet Mn_{12}-tBuAc as a function of the magnetic field component H_{T} transverse to the molecule's easy axis. When the spin is near a magnetic quantum tunneling resonance, we find that Γ increases abruptly at certain values of H_{T}. These increases are observed just beyond values of H_{T} at which a geometric-phase interference effect suppresses tunneling between two excited energy levels. The effect is washed out by rotating H_{T} away from the spin's hard axis, thereby suppressing the interference effect. Detailed numerical calculations of Γ using the known spin Hamiltonian accurately reproduce the observed behavior. These results are the first experimental evidence for geometric-phase interference in a single-molecule magnet with true fourfold symmetry.
    Physical Review Letters 02/2013; 110(8):087205. · 7.73 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A theoretical study into the effect of stationary magnetization induced in a paramagnetic medium by propagation of a circularly-polarized acoustic wave is reported. We termed this magnetoacoustic phenomenon “the inverse acoustic Faraday effect” for its obvious similarity to the inverse Faraday effect in electrodynamics (magnetooptics, in particular). A phenomenological relation is established between the inverse acoustic Faraday effect and the paramagnetic acoustic Faraday rotation widely known as the acoustic Faraday effect. This relation is demonstrated for single molecule magnets. We estimated the magnetization induced by the inverse acoustic Faraday effect in single molecule magnets Mn12–Ac, for the case of a hypersonic wave. This value proved sufficient for the effect to be observed experimentally.
    Physics of Condensed Matter 01/2013; 86(5). · 1.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We propose and analyze a novel scheme to realize the large Kerr nonlinearity via electromagnetically induced transparency (EIT) in molecular magnets. This scheme uses two magnetic fields to induce spin coherence. We obtain the analytical expressions of linear susceptibility, self-Kerr, cross-Kerr susceptibility, phase shift and absorption coefficients. Last, we investigate the nonlinear dynamics of the weak field, and show that the dark and bright microwave soliton can form in the magnetic medium.
    Optics Communications 03/2012; · 1.44 Impact Factor

Full-text

View
0 Downloads
Available from